Incompressible water
Incompressible water
(OP)
Can someone explain when and under what assumptions can we consider water as an incompressible liquid as oppose to considering it a saturated mixture or saturated vapor/liquid?
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RE: Incompressible water
Where you are within the liquid region of a phase diagram doesn't make much difference to compressibility.
David Simpson, PE
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. —Galileo Galilei, Italian Physicist
RE: Incompressible water
and you"ll see under what conditions water is not, as you say, a saturated mixture or a saturated vapor/liquid.
RE: Incompressible water
RE: Incompressible water
RE: Incompressible water
Water ain't solid. Except as an approximation. When you need an approximation. When the "error" inside that assumption of an approximation is less than the accuracy of the approximation of the answer you have decided you can accept within your answer for the safety and operation of your answer.
Thus, in a "solid" reactor piping system, when the sun heats the hull of the submarine which heats the piping in the reactor compartment, the pipe heats up and expands a little bit, the water heats up because the pipe heated up but expands a little bit more, and the pressure of the reactor system goes up. You take a sample of the reactor water, drain a little bit of water from the sample system, the water pressure goes down. You pump a little water into the reactor system with the charging pump to make up for the drained water, the pressure goes up.
Was the water solid? Not really. It has a little bit of a expansion "spring" effect you have to plan for. The pipes and reactor vessel and steam generators also give and expand themselves. That gives you a very, very obvious "spring" effect of relaxation and time delay.
RE: Incompressible water
1) Thermal expansion (if you didnt pressure would increase to infinity - but it is more or less a moot point)
2) Water hammer analysis - if you didnt the pressure surge would be equal to the kinetic energy stored in the liquid moving in the pipe - and that would be very high for most systems.
Best regards, Morten
RE: Incompressible water
http://en.wikipedia.org/wiki/Bulk_modulus
you must get smarter than the software you're using.